I’m new to Unreal, but I imported a scene using datasmith (from 3ds) into Unreal 5.7. The scene looked really good using lumen, so I thought I should set about baking the lighting (the end experience is to be viewed in VR on a quest 3). So I switched to GPU lightmass to do the bake and it ended up looking like this. Has anyone else experienced this? I would have expected some difference to Lumen, but this is wild, even the colour is totally different, the exposure is all over the place, and there doesn’t really seem to be much GI in the lightmass version.
I’ve checked the UV’s on channel 1 and they all seem clean, and played around a ton with all the different settings, but both GPU and CPU lightmass look like this blue overexposed, nasty render.
Are these huge meshes? ( Like the building is one mesh ). Lumen will have a pretty good go at most things you throw at it, but lightmass expects modular meshes with good lightmap UVs, of the right density.
If you do have individual meshes ( like those window frames, and separate walls etc ), it should look pretty good with LM, a default directional light and skylight ( no extras for now ). But big meshes will need high lightmap density. That’s the trade off, static light is great shadows, but you can kiss a load of RAM goodbye.
Hiya, yeah all separate. All 4 walls, celling and floor are separate, as are the details like window frames etc. I have the lightmaps set to between 128 and 4096 and I’ve checked out the UV’s for channel 1 and they look really clean and good.
The thing is, I’d sort of understand if the bake (lightmass) looked really blotchy and blurred, like there were not enough samples or the lightmaps were too low resolution, but the render just looks really odd, like over and under exposed, really blue etc. Its really weird.
Yeah was just trying that. You nailed it! I mean the lightmaps are a bit weird/broken, but that is another issue that I can look into, but the lighting and colour is all fixed. Really odd though as I checked in on lots of videos and documents and AI to try to find a solution and never saw anything about substrate. Thank you again for your help.
If you decide to use GPU Lightmass, you basically have to use the community fork (Epic's GPUlightmass - #667 by yujiang.wang) as there are many issues in the one that comes with the engine
